Guest speaker – Auto-immunity: Multiple Sclerosis Flashcards
What type of disease is multiple sclerosis?
Chronic autoimmune disease of the central nervous system
It primarily affects the myelin sheath around neurons.
What happens to the myelin sheath in multiple sclerosis?
Destruction of myelin sheath around neurons
This destruction leads to lesions that can be seen by MRI.
What is sclerosis in the context of multiple sclerosis?
Scar tissue formed from nerve damage
It results in impaired signal transmission along nerves.
List some common symptoms of multiple sclerosis.
- Pain
- Fatigue
- Tingling
- Impaired gait
- Vision problems
- Bladder problems
- Dizziness
- Cognitive and mood problems
- Paralysis
Symptoms vary among individuals.
How does inflammation affect the immune response in multiple sclerosis?
Increased recruitment of other immune cells
Inflammation leads to the crossing of lymphocytes across the blood-brain barrier.
What role do auto-reactive CD4+ T cells play in multiple sclerosis?
They reencounter their specific antigen presented by MHC II in macrophages, leading to demyelination
These cells contribute to the autoimmune nature of MS.
What is relapsing-remitting MS?
Episodes of relapses followed by periods of remission, affecting ~85% of patients
Symptoms may improve during remission but can relapse.
What characterizes primary progressive MS?
Steady increase in disability with no relapse or remission
This type progresses continuously without improvement.
Describe progressive-relapsing MS.
Steady increase in disability with subsequent relapses and no remissions
It combines elements of both progressive and relapsing forms.
What is secondary progressive MS?
Initial relapsing-remitting MS that begins to steadily increase in disability without periods of remission
This often occurs after a period of relapsing-remitting MS.
What methods are used to diagnose MS?
- MRI
- Vision, coordination, sense of balance tests
- Spinal tap/lumbar puncture
- Blood tests
- Evoked potential tests
These tests help rule out other diseases and assess CNS inflammation.
What is the purpose of IFNb therapy in MS treatment?
Reduces relapses by ~30% through various mechanisms
Mechanisms include controlling cytokine secretion and reducing lymphocyte migration.
What are the effects of corticosteroid therapy in MS?
- Immunosuppressant properties
- Reduces inflammation caused by pro-inflammatory cytokines
- Increases apoptosis in lymphocytes
- Reduces migration of leukocytes to the brain
This therapy helps manage acute exacerbations.
How effective is dimethyl fumarate therapy in MS?
Reduces relapses by 50%
It is taken as oral pills and has fewer side effects compared to some other treatments.
What is a potential mechanism of dimethyl fumarate therapy?
- Anti-inflammatory effects
- Suppresses production of pro-inflammatory cytokines
- Stimulates Tregs
- Induces changes in APC maturation and function
This therapy targets multiple aspects of the immune response.
What is a concern with many MS therapies?
They can lead to immunosuppression
This may increase the risk of infections and other complications.
What factors contribute to MS progression?
Multiple factors including genetic, environmental, and immune system components
Understanding these factors is crucial for managing the disease.
Potential mechanisms of IFNb therapy
o Control secretion of pro & anti-inflammatory cytokines
o Reducing ability of lymphocytes to cross blood-brain barrier
o Affect APC function
o May inhibit some T cell differentiation & increase T cell apoptosis
